Leading German newspaper BILD reported this week that Clemens has received an invitation after reaching the semi-finals at the PDC World Championship.
With interest in the sport growing, Germany just needs a top player who can regularly compete with the world's top players, and Clemens could be just the man Germany has been longing for for years.
Porter revealed to Sport1 that no other spots outside the top four in the world rankings have yet been distributed. Only Michael Smith, Michael van Gerwen, Peter Wright and Gerwyn Price are certain to take part for that reason at the moment.
"Clemens is not about to be shortlisted for the Premier League this week," Porter revealed. "We have read that Clemens has been promised a permanent place in the Premier League. Those are big words because nobody has a permanent place. Even Phil Taylor didn't have a permanent spot."
Porter added that it is vital that players are selected for the Premier League only when they are ready. "We want to make sure the players we nominate are fit and ready to play in the Premier League. That is a very different challenge. You travel around Europe for 17 weeks and usually play in front of 10,000 spectators. We have seen players in the past who were not ready. Playing in the Premier League destroyed their careers,'' Porter said.